Electric switch



March 14, 1933. KEMPTON ELECTRIC SWITCH Filed Au 28, 1931' Inventor:

wm w o n m-t mA A H Patented Mar. 14, 1933 UNITED STATES PATENT OFFICE LESLIE A. K EMTTON, OI BRIDGEPOBT, CONNECTICUT, ASSIGNOB TOGENIRAL arm:

COMPANY, A CORPORATION 0.1 NEW YORK ELECTRIC SWITCH Application filed August 28, 1981. Serial No. 559,958.

My invention relates to electric switches and especially to such switches which may be used to control the rate of hat generation of a plurality of heating units by changing the circuit connections of the heating units to the supply source.

The heat generated by a plurality of heating units may be varied by connecting the heat units in parallel, connecting a lesser number of the units in circuit, and connecting the units in series. The change of the circuit connections has been accomplished by providing a switch with a plurality of Sta-- tionary and rotary contacts mounted in different planes to separate the contacts utilized in making the difierent connections. v 7 The object of my invention is to provide a switch for the above purpose which shall be simple in construction, easy to assemble, rugged and economical.

What I believe to be novel and my invention will be better understood by reference to the specification, accompanying drawing,

. and-appended claims.

Fig. 1 is a side elevation of the switch with the cover removed; Fig. 2 is. a planwiew; 3 is a fragmentary detail view of a portion of the switch; Figs, 4, 5, 6 and 7 are circuit diagrams with ,the different connections made by the switch when in difierent positions and Figs. 8 and Q are detail views of a modification of partof the switch.

Base 1 is of molded insulating material.

1 Three stationary contacts 2, 3 and 4 are secured to base 1, 90 apart, with their contact surfaces disposed in a commonplane. Stationary contact 5 .is secured to the base opposite contact 4 but its contact surface is disposed in a plane abovethe common plane of contacts 2. 3 and 4. Auxiliary stationary contact 6 is secured adjacent contact 5 and carries a. spring contact member '7 which projects over the contact surface of stationary contact 5 and is bent-to be in engagement with said contact surface- Base 1 has a central opening with a bushing secured therein to provide a bearing surface for shaft 8 on which the rotor membersare mounted A handle 9 is connected to the upper elnl'pf shaft8 and pointed to serve.

from one position to another by suitable opcrating mechanism, examples of which are well known in the art. w

The polepiece 10 is of the usual construction with two resilient laminae shaped to form arms 11 which are adapted to straddle the contact portions of the stationary contacts 2, 3 and 4 to interconnect them 1n different combinations.

Instead of usin a second rotatingpolepiece which requires additional insulation and space, the stationary contacts 5 and 6 are biased toward each other as shown in Figs. 2 and 3 but are separated and insulated from each other by a disc 13 of insulating material. Disc 13 is secured to the hub 12 on which the polepiece 10 is mounted and adapted to be moved therewith. A slot .14 is provided to permit the engagement of stationary contacts 5 and 6 when the polepiece is in one of its four operative positions. In place of; the slot 14, I may use a piece of metal secured to the edge of the insulating disc 13 to complete the electrical connection between stationary contacts 5 and 6 as shown in Figs. 8 and 9. This method of making the connection between the contacts 5 and 6 is accomplished by bending a flat piece, of metal 14" around the edge of the insulating disc 13 providin contact surfaces on both sidesf, To secure t e metal piece 14 to the insulating disc 13 a projection is pro.- vided on one end which is bent and passed through correspondin openings in the insulating disc. 13 and t e other end of metal I piece 14 and expanded in the latter opening.

- Projections are also provided on the sides,

- thereception of binding screws.

Figs. 1 and 3.

arranged above contact 5 such a distance that there will be suflicientcontact pressure exerted by the spring contact member 7 when metal piece 14* is in position between contacts 5 and 6. With this modification there is the advantage that the spring contact member 7 does not normally engage the insulating disc 13 so does not have any ten'dency to retard the movement of the rotor member.

Contact strips 15 and 16 are connected to stationary contacts 4 and 5 respectively and are provided with threaded apertures for Stationary contacts 3 and 6 are connected by means of a connector 17 which is mounted in a suitable -manner, as in a recess in the underside of base 1. Stationary contacts 2, 3 and 5 are provided with projections from one side having threaded apertures for the reception of binding screws as may be seen in The operation of the switch may best be understood by reference to Figs. 4, 5, 6 and '7. The supply wires 20 and 21 are connected to the stationary contacts 5 and 4 by means of the binding screws threaded in the strips 15 and 16. Two heating units 18 and 19 are connected together at one end and by means of conductor 22 connected to stationary contact 2. The other end of heating unit" 18 is connected to stationary contacts 3 and 6. The other end of heating.

unit 19 is connected to stationary contact 5. When the polepiece 10 is in the position indicated in Fig. 4, "stationary contact 4.- is not engaged and so no current is supplied to the heating units 18 and 19.-',This is the off-position of theswitch.

When the polepiece 10 is turned in a clockwise direction 90 to its next position (Fig. 5) stationary contacts 2 and 4 are connected through the radial arms 11. Slot 14 or metal piece 14 is in such position that a circuit is completed through stationary-contacts 5 and 6. ,Thus a connection -is made from supply conductor 20 through heating units 18 and 19 in parallel to supply conductor 21. This is the high-heat position of the switch.

When the polepiece 1.0 is rotated again in a clockwise direction 90 (Fig. 6) the stationary contacts 2",, 3 and 4' are interconnected by means of radial arms 11. Stationary contacts 5 and6 are separated by the insulating .disc 13. Thus a connection is made from supply conductor 20 through the heating unit or resistor 19 to supply con-.

ductor 21. The'twosides of the heating unit or resistor 18 are connected together so there is no current flow through it. This is the medium-heat position of the switch.

When the polepiece 10 is again rotated in a clockwise direction 90 (Fig. 7 stationary contacts, 3 and 4 are connected by radial part in arms 11 and stationary contacts and 6 are separated by insulating disc 13. Thus a connection is made from supply conductor 20 through the heating units or resistors 19 and '18 in series to supply conductor 21. This is the low-heat position of the switch.

The circuit connections for the three different rates of heat generation are accomplished by a polepiece which controls the connection of the comomn ends of the heatnection of the opposite ends of the heating units together except in the high-heat position when they are connected in parallel Thus by the use of the disc 13 a switch having only one polepiece may be utilized to control the "connections of heating units to generate heat at three different rates which makes it possible. to make the switch small, of few parts, easy to assemble and simple in construction.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An electric switch comprising a base of insulating material, three i stationary contacts secured to said base 90 apart and having contact surfaces in the sameplane, a polepiece having three radial projecting arms and adapted to engage the contact surfaces of said three stationary contacts in different combinations, a fourth stationary contact secured to the base opposite one of the three stationary contacts with its contact surface in a different plane, from the common plane of the three stationary contacts, an auxiliary stationary contact secured adjacent the fourth stationary contact having a resilient arm projecting over the contact surface of said fourth stationary contact, and a disc of I to the base adjacent the fourth stationary contact having, a resilient arm projecting over the contact surface of said fourth stationary contact surface, and a disc of insulating material'mounted on said rotor and sepexcept in one position.

3. An electric switch comprising a base i arating said fourth and auxiliary contacts polepiece carried by the member to establish circuits through the contacts from a source of current supply, a air of stationary contacts arranged one a ove the other, and a disc mounted on the member to turn there- 'with and extending between said pair of stationary contacts to insulate them from each other except in a predetermined position of the member.

4. An electric switch comprising a base of insulating material, angularly spaced stationary contacts mounted on the base, a rotary member, a polepiece carried by the member for successively engaging the stationary v contacts to establish a circuit through them from a source of supply, a pair of stationary contacts arranged one above the other, a thin disc of insulating material carried by the member and movable between the pair of contaets to normally insulate them from each other and means associated with the disc to establish a circuit at some predetermined position of the "member through said pair of contacts.

In witness whereof, I have hereunto set In hand.

y LESLIE A.- KEMPTON. I 

